More Ads for one. I know in DC Metro (where I am) the ads are insanely small and you could definitely increase ad space on the subway and buses. Cram Ads down people in order to pay for the transit system.
Have we been riding the same metro? The DC metro has some pretty big ads in the stations.
I can't imagine anyone complaining about more/bigger ads on buses, especially if it helps reduce subsidies and spending.